Mask assembly and headgear

ABSTRACT

A mask assembly suitable for the treatment of sleep disordered breathing may include a mask to provide pressurized air to a patient; upper and lower slot features located on each side of the mask; a headgear assembly including a back portion; a pair of upper straps provided to the back portion, each upper strap having a loop portion and a hook portion at a free end thereof for releasably attaching to the loop portion; a pair of lower straps extending away from the back portion, each lower strap having a loop portion and a hook portion at a free end thereof for releasably attaching to the loop portion; and a connection region of each loop portion of each strap, the connection region being adapted to receive a respective hook portion, the connection region being wider than each respective hook portion along each respective hook portion&#39;s entire length.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/472,557, filed Mar. 29, 2017, pending, which is a continuation ofU.S. application Ser. No. 13/938,807, filed Jul. 10, 2013, now U.S. Pat.No. 9,636,476, which is a continuation of U.S. application Ser. No.12/805,787, filed Aug. 19, 2010, now U.S. Pat. No. 8,505,538, which is adivision of U.S. application Ser. No. 11/701,362, filed Feb. 2, 2007,now U.S. Pat. No. 7,802,573, which is a continuation of U.S. applicationSer. No. 10/433,779, filed Nov. 13, 2003, now U.S. Pat. No. 7,188,620,which is a national phase of International Application No.PCT/AU01/01607, filed Dec. 12, 2001, which claims the benefit of U.S.Provisional Application No. 60/254,537, filed Dec. 12, 2000, eachincorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The invention relates to headgear for use with a mask suitable for thedelivery of non-invasive positive pressure ventilation and for nasalCPAP treatment of sleep disordered breathing conditions such asobstructive sleep apnea.

Description of Related Art

Obstructive Sleep Apnea (OSA) is a disease characterised by excessivedaytime sleepiness, loud snoring and daytime irritability. Other effectsof OSA can include depression, high blood pressure, serious heartconditions, sexual problems, memory lapses, intellectual deteriorationand morning headaches.

The treatment of OSA by the application of nasal Continuous PositiveAirway Pressure (CPAP) was invented by Sullivan and is described in U.S.Pat. No. 4,944,310 (Sullivan, assigned to ResMed Limited). The techniqueinvolves the application of a flow of pressurised breathable gas(typically room air) to either the nose or nose and mouth of a patientwhile they sleep. The technique is said to “splint” open the airways.Typical treatment pressures are in the range of 3 to 20 cmH2O. Flows areup to approximately 200 L/min. The flow of pressurised air is producedby a blower and delivered to the patient via a patient interface. Theblower and patient interface are joined by a conduit. Whilst there areother techniques for the treatment of OSA, such as surgery, the use ofCPAP has become the “gold” standard.

For a particular patient, the pressure which is needed to maintain openairways can vary throughout the night and vary on different nights, U.S.Pat. No. 5,245,995 (Sullivan and Lynch, assigned to ResMed Limited)describes a method and device for varying the pressure in accordancewith indications. For example, if the patient starts to snore, thepressure automatically increases, whilst in the absence of snoring, thepressure automatically decreases.

Non-Invasive Positive Pressure Ventilation (NIPPV) is another form oftreatment for breathing disorders. In its most basic form, it involves arelatively higher pressure of gas being provided in the patient maskduring the inspiratory phase of respiration and a relatively lowerpressure or atmospheric pressure being provided in the patient maskduring the expiratory phase of respiration. Typical treatment pressuresare in the range of 3 to 30 cmH, 0.

In other NIPPY modes, the pressure can be made to vary in a complexmanner throughout the respiratory cycle. For example, the pressure atthe mask during inspiration or expiration can be varied through theperiod of treatment, as disclosed in international PCT patentapplication no. PCT/AU97/0061 (Berthon-Jones, assigned to ResMedLimited).

In this specification, any reference to CPAP is to be understood asembracing all of the above-described forms of ventilatory treatment orassistance.

One of the earliest patient interfaces for providing CPAP treatment wasconstructed to include a fibreglass model of the patient's nose. Themodel was adhered to the patient's nose each night and removed eachmorning. An advantage of this patient interface included the customisedfit, which assisted in a good seal between the patient interface and thepatient's airways. However, the use of adhesive to secure the mask wasinconvenient and not desirable.

Another suitable patient interface is described in U.S. Pat. No.5,243,971 (Sullivan and Bruderer, assigned to the University of Sydney),entitled “Nasal Mask for CPAP having Ballooning/Moulding Seal withWearer's Nose and Facial Contours”. This patent describes a nasal maskwith a soft face-contacting portion, and a rigid shell. The mask is heldin position using headgear. The headgear is attached to the mask andpasses around the back of the wearer's head. The patent depicts two setsof straps in the headgear. The first set comprised a pair of strapspassing from the forehead region to the back of the head. The second setcomprised a pair of straps passing from the nasal region of the mask tothe back of the head.

Another known patient interface is the MIRAGE® nasal mask (by ResMedLtd). This nasal mask includes a pair of headgear attachment points inthe nasal region of the mask shell and a forehead support that includesanother pair of headgear attachment points. The headgear includes asingle piece of a soft, flexible composite fabric with a generallytriangular back portion and four straps. The four straps include a pairof upper straps and a pair of lower straps connecting to the headgearattachment points on the forehead support and nasal mask shellrespectively. At the end of each strap is secured a piece of hookmaterial, which, in use, passes through a headgear attachment point andfastens on corresponding loop material on the strap. The generallytriangular back portion engages the skull in the region of the occiput.The fabric stretches under a load. The base of the triangle ispositioned near and generally in line with the upper straps. Each strapis approximately 2 cm wide and approximately 3 mm thick. The fabric is acomposite of three layers. The inner layer, closest to the patient'shead, is made from nylon. The middle layer is made from neoprene. Theouter layer is made from loop material, suitable for engaging with hookfastening material such as Velcro™. The upper straps have an approximatelength of 19 cm, from the end to the closest corner of the triangle,whilst the lower straps have an approximate length of 26 cm. Includingthe triangle, the upper and lower straps each have an approximate totallength of 60.5 cm. The triangular back portion is an approximateisosceles triangle, with a base of approximately 13.5 cm and sides ofapproximately 9 cm.

Some patients open their mouths during sleep, which means that they maynot receive the benefit of CPAP due to mouth leaks. Various solutionshave been proposed for this problem. One solution is taught in U.S. Pat.No. 6,123,082 (Berthon-Jones, assigned to ResMed Limited), whereby thelips are held closed. Another solution is to use a mask that covers boththe nose and mouth of the patient. An example of a mouth and nasal maskis described in U.S. Pat. No. 5,560,354 (Berthon-Jones, Calluaud, Lynch& Hely, assigned to ResMed Limited).

Another suitable mask system is the MIRAGE® full-face mask (by assigneeResMed Limited). The MIRAGE® full-face mask and headgear is illustratedin FIGS. 1, 2 and 3. Suitable headgear (102) for this mask (100) isconstructed from a composite material of nylon, neoprene and loopmaterial. The headgear similarly comprises a pair of upper (104) and apair of lower straps (106) and a generally triangular back portion(108). The upper strap has a total length of approximately 610 mm asshown in FIG. 3. The straps have an approximate width of 25 mm, however,the upper strap has an approximate width of 19 mm. The triangular regionhas a base of approximately 15.5 cm and two equal sides of approximately11 cm. The upper and lower straps are approximately 192 mm apart. Inaddition, the headgear includes a quick release mechanism (110), asdescribed in the pending U.S. patent application Ser. No. 09/482,718(Lithgow, assigned to ResMed Limited). The quick release mechanismprovides a “rip-chord” that can be pulled upon to separate the headgearand remove the mask in an emergency. When the headgear is positioned onthe patient's head, the quick-release mechanism is situated at the backof the head and the chord runs through loops towards the front of themask system.

Patient interface arrangements include nasal masks, nose and mouthmasks, nasal prongs and nasal pillows. In all forms of patient interfaceused with CPAP for treating sleep disordered breathing, there is a needto counterbalance the force of the pressurised air and to correctlyposition the interface. Since the patient must sleep with thisinterface, it is important that it be comfortable. From themanufacturing and distribution channel perspectives, it is advantageousif one size of headgear fits a large range of head shapes and sizes.

It should be noted that while there are many mask and headgeararrangements available for ventilators, respirators, aviator masks andother breathing apparatus, in general, these may not be suitable for usein the treatment of sleep disordered breathing because they are notsufficiently comfortable to allow the patient to sleep.

The present invention is directed towards providing headgear for holdingand securing a mask for use in the treatment of sleep disorderedbreathing which improves patient comfort, is long lasting and fits awide range of head shapes and sizes.

BRIEF SUMMARY OF THE INVENTION

The invention provides headgear for securing and positioning a masksuitable for the treatment of sleep disordered breathing with thefollowing advantageous combination of features:

-   (i) Constructed from a composite including polyurethane foam-   (ii) Relatively narrow strap ends,-   (iii) Displaced lower strap,-   (iv) A quick release mechanism near the front of the face; and-   (v) Additional attached components to alter the elasticity and    stiffness of the straps.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a front three-quarter view of a MIRAGE® full-face mask andprior art headgear system in position on a patient's head.

FIG. 2 shows a rear three-quarter view of a MIRAGE® full-face mask andprior art headgear system on a patient's head.

FIG. 3 shows a view of prior art full-face mask headgear laid flat.

FIG. 4 shows a view of headgear according to an embodiment of thepresent invention.

FIG. 5 shows a view of the quick release mechanism according to thepresent invention.

FIG. 6A shows a view of a mask headgear strap in accordance with thepresent invention laid flat.

FIG. 6B shows a view of a mask headgear strap in accordance with thepresent invention laid flat.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides headgear (10) for securing and positioning a masksuitable for the treatment of sleep disordered breathing.

(i) Material

The headgear is constructed from a composite of polyurethane foam, loopmaterial and hook material whose shape includes a pair of upper straps(20) and lower straps (30) and a generally triangular back portion (40).A piece of hook material (22) is attached to the end of each of the fourstraps so that the straps may be secured to the attachment points on themask. The end includes a main body (23) and a tapered free end portion(25).

The composite has three layers. The first layer, which in use ispositioned against the head of the patient, is constructed frompolyester or nylon fabric. The second, middle layer is constructed froman hypoallergenic breathable polyurethane foam. The third layer isconstructed from loop material. A suitable material for constructing thecomposite is BREATH-O-PRENE® manufactured by ACCUMED, New York, UnitedStates of America. The total thickness of the composite is approximately2 mm. The upper and lower pairs of straps are approximately 150 mm apartwhen laid flat. The upper and lower straps have an approximate totallength (from the left side to the right side) of 610 mm.

The generally triangular back portion (40) of the headgear (10) isconstructed and arranged to engage generally with the occiput of thepatient's head in use. In use, the base of the triangle is positioned atthe crown of the head, while the apex of the triangle lies generallyjust above the point of contact between the skull and the muscles of theneck.

(ii) Relatively Narrow Strap Ends

The headgear of the present invention is configured to minimize thediscomfort associated with the use of hook material. In prior artheadgear, that discomfort can arise where the hook material may be incontact with the patient's skin, say the cheek or neck regions, forextended periods of time. That undesirable contact will occur where thehook material, to some extent is not entirely located on the receivingloop material, but lies tangential to the loop material, and to someextent extends beyond the loop material and comes in contact with thepatient's skin, either continuously while the headgear is in use or whenit is compressed against the skin, as can occur when the patient headchanges position during the sleep period.

As shown in FIG. 4, the width of each lower strap is constant forapproximately half their length, forming a relatively wide portion (24),and then over a relatively short distance, changes to a narrower widthfor the remaining half of their length, forming a relatively narrowportion (26), terminating at the point where the hook material (22) isjoined to the composite material. A characteristic of this configurationis that the point of contact where the hook material detachably bindswith the strap loop material is positioned on the wide portion (24) andis wider by approximately 1 cm than the width of the engaging hookmaterial. By adopting this configuration, the target region for bindingis relatively greater in area than is the case with prior art. Prior artheadgear includes a tapered end hook section that is of narrower widththan that of the intended contact loop section of the strap. However,the prior art hook section tapered end is less than one half the lengthof the hook section, that is, it does not represent the majority of thelength of the hook section nor does its length represent the majority ofthe length of the intended corresponding contact loop section (i.e., themaximum extent of the loop section covered by the hook section).

In contrast to the prior art, with the present invention the attachmentof the hook material is facilitated, as relatively less precision isrequired in the placement of the hook section to achieve binding. Thisreduced dependence on precision is of advantage to all persons using theheadgear and is of particular benefit to the user that may be trying tofit the headgear in a home environment and where it is not possible todirectly sight the headgear components they are manipulating.Furthermore, compared to the prior art (where the hook material and thetarget region are of substantially the same width), this configurationreduces the chance of exposing some of the hook material to interferewith the wearer, causing discomfort and possibly skin irritation orabrasion.

(iii) Displaced Lower Strap

A length of each of the left and right lower straps is displacedvertically lower by approximately 1 cm (28). By adopting thisconfiguration, it is possible to optimize the design of the base of theback portion so as to achieve the desired security of attachment butavoid compromising comfort in a situation where the lowest point of theheadgear in the occiput region is extended to a position that is lowerthan is otherwise required in order to achieve a sufficiently loweststrap point. This approach avoids the prior art problem of having theheadgear rear portion extending beyond what would otherwise be requiredand thereby engaging the sensitive area below the occipital lobe.

(iv) Quick Release Mechanism

Preferably the headgear of the present invention includes a quickrelease mechanism (50) (see FIG. 5), and this is especially so when theheadgear is intended to be used with a mask that covers the patient'snose and mouth.

The quick-release mechanism (50) suitable for incorporation into thepreferred embodiment is constructed from a sub-assembly of threecomponents: (i) a release loop of a cord material (52), (ii) a generallyrectangular length of hook material (54), and (iii) a generallyrectangular length of a composite fabric (56) which can bind to the hookmaterial, as discussed above. The sub-assembly is generally rectangularin shape and in use forms an extension of one of the lower straps.Preferably the loop cord is constructed from braided cord about 17 cmlong. The cord loop (52) is sewn to one end of the length of hookmaterial (54). The hook material (54) and composite fabric (56) arejoined at the other end of the hook material (54), preferably via a weldjoint. In use, the end of the hook material (54), to which is connectedthe loop cord (52), is secured, using the hook and loop mechanism, tothe end of a modified lower strap which, in contrast to the lower straps(30) shown in FIG. 4, does not contain hook material. The other end (56)of the quick release mechanism (50) is free to be connected to aheadgear attachment point on the mask shell and releasably attached toan exposed portion of the hook material (54). If it is desired to usethe quick-release mechanism (50), it is convenient for the patient topull down on the loop of braided cord (52), thereby disengaging thelower strap from the mask shell and allowing the mask to then be readilyremoved from the patient's face. A quick-release mechanism of thisconfiguration may be used on headgear that is fabricated of materialsand in configurations that are different to those of the type describedabove and as such is an invention in its own right.

(v) Altering the Stiffness and Extensibility

In one form of the invention, the extensibility of the straps can bealtered by attaching lengths of generally inextensible material (62)such as cotton or silk to the straps, as shown in FIG. 6B. The effect ofthis arrangement is to make the headgear less extensible along thelength of the straps than in a vertical direction. In a preferredembodiment, lengths of cotton are sewn to the straps.

In another form of the invention, the stiffness of the straps can bealtered by attaching stiffening material (64) to the top and bottom edgeof the straps, as shown in FIG. 6A. Alternatively, or in addition, thestrap may be stiffened by any other suitable means including by addingstitching as lines, in a crisscross pattern, or both. This makes theheadgear less “floppy” and more convenient to put on the head of awearer.

In another form of the invention, the headgear is constructed from ananisotropic material that is more extensible in a first direction thanin a direction at an angle of 90 degrees to the first direction. Thisenables the headgear to be cut from a single piece of composite materialand yet have different extensibilities in different directions.Preferably, the headgear will be more extensible in a vertical directionthan in a horizontal direction. Hence the upper and lower straps will beless extensible in a direction along their length than in a directionalong their width. This means that the back portion of the headgear canbe more extensible in a direction from the base of the skull to thecrown, than in a direction at right angles to that direction.

What is claimed is:
 1. A mask assembly suitable for the treatment ofsleep disordered breathing, comprising: a mask configured to providepressurized air to a patient in the range of 3 to 20 cmH2O throughoutthe patient's respiratory cycle, the mask further comprising a soft,face-contacting portion, a rigid shell, a pair of upper headgearattachment points, and a pair of lower headgear attachment points; and aheadgear assembly configured to hold the mask in position on thepatient's face during treatment, the headgear assembly comprising: a topportion; a back portion comprising a bottom portion and a pair of sideportions connecting the top portion and the bottom portion; an openingformed by the top portion, the bottom portion, and the pair of sideportions; a pair of elongated lower straps extending from the backportion and configured to extend below the patient's ears and across thepatient's facial skin in use; a pair of elongated upper straps extendingfrom the back portion and configured to extend above the patient's earsin use; and a transition between the bottom portion and each of the pairof elongated lower straps, the transition being angled downwardlyrelative to the bottom portion such that a lower edge of at least aportion of each of the pair of elongated lower straps is positionedlower on the patient's head than a lower edge of the bottom portion inuse, wherein each of the pair of elongated upper straps and each of thepair of elongated lower straps includes a loop material positioned alongan external surface thereof and a hook material configured to releasablyattach to the loop material to attach the pair of elongated upper strapsand the pair of elongated lower straps to the mask, and wherein the loopmaterial of each of the pair of elongated upper straps and each of thepair of elongated lower straps includes a connection region adapted toattach to the hook material of a corresponding strap, the connectionregion being wider than the hook material such that when the hookmaterial is attached to the loop material, in use, the loop material ateach connection region is configured to shield the patient's facial skinfrom contact with the hook material.
 2. The mask assembly of claim 1,wherein at least a portion of the headgear assembly is constructed of ananisotropic, composite material having different extensibilities indifferent directions.
 3. The mask assembly of claim 1, wherein a lengthof a generally inextensible material is attached to at least a portionof the headgear assembly to reduce extensibility of the headgearassembly.
 4. The mask assembly of claim 1, wherein stitching is added toat least a portion of the headgear assembly to stiffen the headgearassembly.
 5. The mask assembly of claim 4, wherein the stitching isadded as lines, in a crisscross pattern, or both the lines and thecrisscross pattern.
 6. The mask assembly of claim 1, wherein a leadingend of each of the pair of elongated upper straps is configured to passthrough a corresponding one of the pair of upper headgear attachmentpoints and be doubled-back on itself to attach the hook material to theloop material to secure the headgear assembly to the mask, and whereinthe loop material of each of the pair of elongated lower straps isconfigured to pass through a corresponding one of the pair of lowerheadgear attachment points and doubled-back on itself to attach the hookmaterial to the loop material to secure the headgear assembly to themask.
 7. The mask assembly of claim 6, wherein at least a portion of theheadgear assembly is constructed of a composite having a first layer tobe positioned against the patient's head, a second, middle layerconstructed from foam, and a third layer including the loop material. 8.The mask assembly of claim 1, further comprising vent holes adapted tovent exhaled air from the mask.
 9. The mask assembly of claim 1, furthercomprising an elbow connected to the mask, the elbow adapted to deliverpressurized gas to an interior of the mask.
 10. The mask assembly ofclaim 1, wherein the mask is a full face mask.
 11. The mask assembly ofclaim 1, wherein the mask is a nasal mask.
 12. The mask assembly ofclaim 1, wherein the opening is arranged to receive the occiput of thepatient's head.
 13. The mask assembly of claim 1, wherein the maskfurther comprises a forehead support, and wherein the pair of elongatedupper straps are configured to pass from the patient's forehead regionto the back of the patient's head.
 14. The mask assembly of claim 1,wherein: stitching is added to at least a portion of the headgearassembly to stiffen the headgear assembly, the stitching is added aslines, in a crisscross pattern, or both the lines and the crisscrosspattern, a leading end of each of the pair of elongated upper straps isconfigured to pass through a corresponding one of the pair of upperheadgear attachment points and be doubled-back on itself to attach thehook material to the loop material to secure the headgear assembly tothe mask, the loop material of each of the pair of elongated lowerstraps is configured to pass through a corresponding one of the pair oflower headgear attachment points and doubled-back on itself to attachthe hook material to the loop material to secure the headgear assemblyto the mask, at least a portion of the headgear assembly is constructedof a composite having a first layer to be positioned against thepatient's head, a second, middle layer constructed from foam, and athird layer including the loop material, the mask assembly furthercomprises vent holes adapted to vent exhaled air from the mask, the maskassembly further comprises an elbow connected to the mask, the elbowadapted to deliver pressurized gas to an interior of the mask, the maskis a full face mask, and the opening is arranged to receive the occiputof the patient's head.
 15. The mask assembly of claim 14, wherein atleast a portion of the headgear assembly is constructed of ananisotropic, composite material having different extensibilities indifferent directions.
 16. The mask assembly of claim 14, wherein each ofthe pair of elongated upper straps includes a first portion and a secondportion, each first portion being wider than each second portion, andwherein each first portion is proximal to the back portion and eachsecond portion is distal from the back portion.
 17. The mask assembly ofclaim 16, wherein the transition between the bottom portion and each ofthe pair of elongated lower straps has a curvature extending away fromthe back portion in a longitudinal direction.
 18. The mask assembly ofclaim 1, wherein: stitching is added to at least a portion of theheadgear assembly to stiffen the headgear assembly, the stitching isadded as lines, in a crisscross pattern, or both the lines and thecrisscross pattern, a leading end of each of the pair of elongated upperstraps is configured to pass through a corresponding one of the pair ofupper headgear attachment points and be doubled-back on itself to attachthe hook material to the loop material to secure the headgear assemblyto the mask, the loop material of each of the pair of elongated lowerstraps is configured to pass through a corresponding one of the pair oflower headgear attachment points and doubled-back on itself to attachthe hook material to the loop material to secure the headgear assemblyto the mask, at least a portion of the headgear assembly is constructedof a composite having a first layer to be positioned against thepatient's head, a second, middle layer constructed from foam, and athird layer including the loop material, the mask assembly furthercomprises vent holes adapted to vent exhaled air from the mask, the maskassembly further comprises an elbow connected to the mask, the elbowadapted to deliver pressurized gas to an interior of the mask, the maskis a nasal mask, and the opening is arranged to receive the occiput ofthe patient's head.
 19. The mask assembly of claim 18, wherein at leasta portion of the headgear assembly is constructed of an anisotropic,composite material having different extensibilities in differentdirections.
 20. The mask assembly of claim 18, wherein each of the pairof elongated upper straps includes a first portion and a second portion,each first portion being wider than each second portion, and whereineach first portion is proximal to the back portion and each secondportion is distal from the back portion.
 21. The mask assembly of claim1, wherein the headgear assembly is constructed from a single piece ofcomposite material.
 22. A mask assembly suitable for the treatment ofsleep disordered breathing, comprising: a mask configured to providepressurized air to a patient in the range of 3 to 20 cmH2O throughoutthe patient's respiratory cycle, the mask further comprising a soft,face-contacting portion, a rigid shell, a pair of upper headgearattachment points, and a pair of lower headgear attachment points; and aheadgear assembly configured to hold the mask in position on thepatient's face during treatment, the headgear assembly comprising: a topportion; a back portion comprising a bottom portion and a pair of sideportions connecting the top portion and the bottom portion; an openingformed by the top portion, the bottom portion, and the pair of sideportions; a pair of elongated lower straps connected to the back portionand configured to extend below the patient's ears and across thepatient's facial skin in use; a pair of elongated upper straps connectedto the back portion and configured to extend above the patient's ears inuse; and a transition between the bottom portion and each of the pair ofelongated lower straps, the transition being angled downwardly relativeto the bottom portion such that a lower edge of at least a portion ofeach of the pair of elongated lower straps is positioned lower on thepatient's head than a lower edge of the bottom portion in use, a lengthof a generally inextensible material is attached to at least a portionof the headgear assembly to reduce extensibility of the headgearassembly, stitching is added to at least a portion of the headgearassembly to stiffen the headgear assembly, the stitching is added aslines, in a crisscross pattern, or both the lines and the crisscrosspattern, each of the pair of elongated upper straps and each of the pairof elongated lower straps include a loop material positioned along anexternal surface thereof and a hook material configured to releasablyattach to the loop material to attach the pair of elongated upper strapsand the pair of elongated lower straps to the mask, the loop material ofeach of the pair of elongated upper straps and each of the pair ofelongated lower straps includes a connection region adapted to attach tothe hook material of a corresponding strap, the connection region beingwider than the hook material such that when the hook material isattached to the loop material, in use, the loop material at eachconnection region is configured to shield the patient's facial skin fromcontact with the hook material, a leading end of each of the pair ofelongated upper straps is configured to pass through a corresponding oneof the pair of upper headgear attachment points and be doubled-back onitself to attach the hook material to the loop material to secure theheadgear assembly to the mask, the loop material of each of the pair ofelongated lower straps is configured to pass through a corresponding oneof the pair of lower headgear attachment points and doubled-back onitself to attach the hook material to the loop material to secure theheadgear assembly to the mask, at least a portion of the headgearassembly is constructed of a composite having a first layer to bepositioned against the patient's head, a second, middle layerconstructed from foam, and a third layer including the loop material,the mask assembly further comprises vent holes adapted to vent exhaledair from the mask, the mask assembly further comprises an elbowconnected to the mask, the elbow adapted to deliver pressurized gas toan interior of the mask, the mask is a full face mask, the opening isarranged to receive the occiput of the patient's head, the mask furthercomprises a forehead support, and the pair of elongated upper straps areconfigured to pass from the patient's forehead region to the back of thepatient's head.
 23. The mask assembly of claim 22, wherein at least aportion of the headgear assembly is constructed of an anisotropic,composite material having different extensibilities in differentdirections.
 24. The mask assembly of claim 22, wherein the transitionbetween the bottom portion and each of the pair of elongated lowerstraps has a curvature extending away from the back portion in alongitudinal direction.
 25. A mask assembly suitable for the treatmentof sleep disordered breathing, comprising: a mask configured to providepressurized air to a patient in the range of 3 to 20 cmH2O throughoutthe patient's respiratory cycle, the mask further comprising a soft,face-contacting portion, a rigid shell, a pair of upper headgearattachment points, and a pair of lower headgear attachment points; and aheadgear assembly configured to hold the mask in position on thepatient's face during treatment, the headgear assembly comprising: a topportion; a back portion comprising a bottom portion and a pair of sideportions connecting the top portion and the bottom portion; an openingformed by the top portion, the bottom portion, and the pair of sideportions; a pair of elongated lower straps connected to the back portionand configured to extend below the patient's ears and across thepatient's facial skin in use; a pair of elongated upper straps connectedto the back portion and configured to extend above the patient's ears inuse; and a transition between the bottom portion and each of the pair ofelongated lower straps, the transition being angled downwardly relativeto the bottom portion such that a lower edge of at least a portion ofeach of the pair of elongated lower straps is positioned lower on thepatient's head than a lower edge of the bottom portion in use, wherein:a length of a generally inextensible material is attached to at least aportion of the headgear assembly to reduce extensibility of the headgearassembly, each of the pair of elongated upper straps and each of thepair of elongated lower straps include a loop material positioned alongan external surface thereof and a hook material configured to releasablyattach to the loop material to attach the pair of elongated upper strapsand the pair of elongated lower straps to the mask, the loop material ofeach of the pair of elongated upper straps and each of the pair ofelongated lower straps includes a connection region adapted to attach tothe hook material of a corresponding strap, the connection region beingwider than the hook material such that when the hook material isattached to the loop material, in use, the loop material at eachconnection region is configured to shield the patient's facial skin fromcontact with the hook material, a leading end of each of the pair ofelongated upper straps is configured to pass through a corresponding oneof the pair of upper headgear attachment points and be doubled-back onitself to attach the hook material to the loop material to secure theheadgear assembly to the mask, the loop material of each of the pair ofelongated lower straps is configured to pass through a corresponding oneof the pair of lower headgear attachment points and doubled-back onitself to attach the hook material to the loop material to secure theheadgear assembly to the mask, at least a portion of the headgearassembly is constructed of a composite having a first layer to bepositioned against the patient's head, a second, middle layerconstructed from foam, and a third layer including the loop material,the mask assembly further comprises vent holes adapted to vent exhaledair from the mask, the mask assembly further comprises an elbowconnected to the mask, the elbow adapted to deliver pressurized gas toan interior of the mask, the mask is a nasal mask, the opening isarranged to receive the occiput of the patient's head, the mask furthercomprises a forehead support, and the pair of elongated upper straps areconfigured to pass from the patient's forehead region to the back of thepatient's head.
 26. The mask assembly of claim 25, wherein at least aportion of the headgear assembly is constructed of an anisotropic,composite material having different extensibilities in differentdirections.
 27. The mask assembly of claim 25, wherein the transitionbetween the bottom portion and each of the pair of elongated lowerstraps has a curvature extending away from the back portion in alongitudinal direction.
 28. A mask assembly suitable for the treatmentof sleep disordered breathing, comprising: a mask configured to providepressurized air to a patient in the range of 3 to 20 cmH2O throughoutthe patient's respiratory cycle, the mask further comprising a soft,face-contacting portion, a rigid shell, a pair of upper headgearattachment points, and a pair of lower headgear attachment points; and aheadgear assembly configured to hold the mask in position on thepatient's face during treatment, the headgear assembly comprising: a topportion configured to be positioned superior to the occiput of thepatient's head in use; a back portion comprising a bottom portionconfigured to be positioned inferior to the occiput of the patient'shead in use; a pair of side portions between the top portion and thebottom portion; a pair of elongated lower straps connected to the backportion and configured to extend below the patient's ears and across thepatient's facial skin in use; a pair of elongated upper straps connectedto the back portion and configured to extend above the patient's ears inuse; and a transition between the bottom portion and each of the pair ofelongated lower straps, the transition being angled downwardly relativeto the bottom portion such that a lower edge of at least a portion ofeach of the pair of elongated lower straps is positioned lower on thepatient's head than a lower edge of the bottom portion in use, wherein:each of the pair of elongated upper straps and each of the pair ofelongated lower straps include a loop material positioned along anexternal surface thereof and a hook material configured to releasablyattach to the loop material to attach the pair of elongated upper strapsand the pair of elongated lower straps to the mask, the loop material ofeach of the pair of elongated upper straps and each of the pair ofelongated lower straps includes a connection region adapted to attach tothe hook material of a corresponding strap, the connection region beingwider than the hook material such that when the hook material isattached to the loop material, in use, the loop material at eachconnection region is configured to shield the patient's facial skin fromcontact with the hook material, a leading end of each of the pair ofelongated upper straps is configured to pass through a corresponding oneof the pair of upper headgear attachment points and be doubled-back onitself to attach the hook material to the loop material to secure theheadgear assembly to the mask, the loop material of each of the pair ofelongated lower straps is configured to pass through a corresponding oneof the pair of lower headgear attachment points and doubled-back onitself to attach the hook material to the loop material to secure theheadgear assembly to the mask, at least a portion of the headgearassembly is constructed of a composite having a first layer to bepositioned against the patient's head, a second, middle layerconstructed from foam, and a third layer including the loop material,the mask assembly further comprises vent holes adapted to vent exhaledair from the mask, the mask assembly further comprises an elbowconnected to the mask, the elbow adapted to deliver pressurized gas toan interior of the mask, the mask is a nasal mask, the mask furthercomprises a forehead support, and the pair of elongated upper straps areconfigured to pass from the patient's forehead region to the back of thepatient's head.
 29. The mask assembly of claim 28, wherein at least aportion of the headgear assembly is constructed of an anisotropic,composite material having different extensibilities in differentdirections.
 30. The mask assembly of claim 28, wherein each of the pairof elongated lower straps includes a first portion and a second portion,each first portion being wider than each second portion, and whereineach first portion is proximal to the back portion and each secondportion is distal from the back portion.